Muscleblind facilitates kinesin dependent RNA localization in neurons

项目摘要/摘要 RNA定位和局部蛋白质合成使高度分化的有丝分裂后细胞，如神经元，能够 及时、高效地应对外界干扰，调整专业隔间的蛋白质水平 举止。适当的RNA定位和局部翻译对于作为学习基础的神经元功能是必要的 和记忆。强直性肌营养不良1型(DM1)在世界范围内每8000人中就有一例感染，是 其中RNA错误定位可能有助于疾病的进展。而DM1的肌肉症状有 经过彻底研究，DM1患者还表现出多种削弱中枢神经系统的症状，例如 睡眠过多、快感减退和神经认知/行为障碍。阐明其基本机制是至关重要的 在健康神经元中的RNA定位以更好地了解与疾病相关的中枢神经系统症状 涉及RNA错误定位，如DM1。在这个拟议的项目中，我们计划利用多方面的方法 它结合了多种成像和生化技术。野生型小鼠的原代皮质神经元 胚胎大脑将作为我们的主要模型。巴塞尔实验室在研究RNA方面有广泛的背景 生物学，并发表了大量关于RNA结合蛋白(RBPs)脆性X心理的作用 运动神经元(SMN)蛋白的发育迟缓(FMRP)和存活 疾病。本项目的目的是阐明特定的RBP在DM1发病机制中的作用。 作为mRNA从细胞体定位到突触前区的促进剂。 我们假设MBNL在其信使核糖核酸和特定的运动蛋白马达蛋白(KIFs)之间起到了适配器的作用。 之所以选择激动素而不是其他马达蛋白作为这项提案的重点，是因为众所周知 动蛋白有助于细胞货物远离胞体的长距离顺行移动。另一个 该项目的目标是确定与MBNL相互作用的特定KIF，以将靶mRNA转录本输送到 神经元内的适当目的地。根据货物和目的地，某些基夫或基夫的组合 可能是适当运输所必需的。这项工作将加深我们对RNA本地化和 限制性商业惯例在这一进程中发挥的作用。这项研究还将激励未来的研究，以确定各种 RNA转运颗粒的成分，不仅是定位所必需的，也是颗粒形成所必需的， 锚定和拆卸。从这个项目中获得的知识可以应用于病理情况。 这是由于RNA错误定位引起的，例如DM1。

PROJECT SUMMARY/ABSTRACT RNA localization and local protein synthesis enable highly differentiated, post-mitotic cells, such as neurons, to respond to external perturbations and adjust protein levels in specialized compartments in a timely and efficient manner. Proper RNA localization and local translation are necessary for neuronal functions that underlie learning and memory. Myotonic Dystrophy Type 1 (DM1), which affects 1 in 8000 worldwide, is an example of disease in which RNA mislocalization may contribute to disease progression. While the muscular symptoms of DM1 have been thoroughly studied, DM1 patients also present with multiple debilitating CNS symptoms, such as hypersomnia, anhedonia, and neurocognitive/behavioral disorders. It is critical to elucidate the basic mechanism of RNA localization in healthy neurons to better understand the CNS symptoms associated with a disease involving RNA mislocalization, such as DM1. In this proposed project, we plan to utilize a multi-faceted approach that combines multiple imaging and biochemical techniques. Primary cortical neurons from wild type mouse embryonic brains will serve as our principal model. The Bassell Lab has extensive background in studying RNA biology and has published extensively on the roles of the RNA-Binding Proteins (RBPs) Fragile X Mental Retardation (FMRP) and Survival of Motor Neuron (SMN) proteins which are also affected in related neurological diseases. The goal of this project is to elucidate the role that a specific RBP implicated in DM1 pathogenesis, Muscleblind (MBNL), has as a facilitator of mRNA localization from the cell body to pre-synaptic compartments. We hypothesize that MBNL acts an adaptor between its mRNA cargo and specific kinesin motor proteins (Kifs). Kinesin was chosen over other motor proteins as the focus of this proposal because it is well-established that kinesins facilitate the long distance anterograde movement of the cellular cargo away from the soma. Another goal of this project is to identify the specific Kifs that interact with MBNL to transport target mRNA transcripts to proper destinations within neurons. Depending on the cargo and destination, certain Kifs or combinations of Kifs might necessary for proper transportation. This work will strengthen our understanding of RNA localization and the role that RBPs play in this process. This research will also motivate future studies to identify various components of RNA transport granules, necessary not only for localization, but also granule formation, anchoring, and disassembly. The knowledge gained from this project could be applied to pathological conditions that arise due to RNA mislocalization, such as DM1.